Coleman sellers



-o.sBLLERs. EXHIBITING STEREOSCOPIG PIGTURES 0P MOVING OBJECTS.

Patented Feb 5, 1-861.

UNITED srarn sggrnn r COLEMAN SELLERS, OF PHILADELPHIA, PENNSYLVANIA,ASSIUXOR TO HIMSELF AND G. BUHNHAM, OF SAME PLACE.

EXHIBITING STEREOSCOPIC PICTURES OF .MOVING OBJECTS.

' Specification of Letters Patent No. 81,857, dated February 5, 1861.

T 0 all whom it may concern:

Be it known that I, COLEMAN SnLLnRs, of the city of Philadelphia, in theState of Pennsylvania, have invented a new and useful Improvement in theMode of Exhibiting Stereoscopic Pictures of Moving Objects; and I dodeclare that the following is a full and exact description of the mode,reference being made to the annexed drawings, making a part of thisspecification, and

which can be understood as they are described during the progress of thespecification.

IVhat I aim to accomplish is as I have above stated, to so exhibitstereoscopic pictures as to make them represent objects in motion suchas the revolving wheels of machinery, and various motions of the humanbody, adding to the wonders of that marvelous invention the stereoscopea semblance of life that can only come from motion. It is to breatheinto the statue like forms of the stereograph as it were, the breath oflife. It may have occurred to many the possibility of effecting thisdesirable result, and the phantasmascope gives a clue to the manner ofaccomplishment of it. That is, that it must be done by viewing in succession a series of pictures (taken in different positions of the movingobject) with sufficient rapidity to insure the image of one beingretained on the retina until the next one is brought into view. This hasfrequently been done with plane pictures but has never been, withstereoscopic pictures, nor can it be done with them in the usual mannerof exhibiting such pictures. In the phantasmascope as it is usuallyconstructed, the pictures are arranged in a circle on a card board, andthe pictures are viewed through holes corresponding in number to thepictures. In these toys, the pictures pass before the eye, and are seenfor a greater or less time, according to the size of the holes, and ithas been found that unless the holes are very small, there is a blurringeffect produced. On this plan my first instruments were designed, thatis, I arranged a series of stereoscopic pictures around a cylinder, andmade use of various cut off devices to produce the instantaneous visionsrequired, but in all cases, though I found the appearance of motion wasproduced, yet there was a blurring of the image that prevented my seeingthe fine detail of the picture. After a long series of experiments Imade the discovery that it is abso lutely necessary, that the picturesshould be entirely at rest during the moment of vision or that motionshould be in a direction of the line of vision, that is, advancingtoward the eye, or receding from it, just as you would take a card inboth hands, and move it rapidly to and from you, in contradistinction tomoving it from right to left, or up and down.

In order to explain how I reduce my dis covery to practice I willproceed to describe an instrument which in the simplest manner iscapable of showing the principle of my invention.

Referring to Figure l of the annexed drawing which represents aperspective view of the instrument consisting of a cylinder case A,provided with an eye piece B, containing the usual stereoscope prisms CO. and a shield to protect the eyes from outside light. The cylinder Ais cut away on two sides :L to admit light into the inside. IYithin thecylinder is arranged a series of wings E E radiating from av centerspindle D. On these wings are grooves K, K, into which the stereographsare put. Around the outside of these radial wings is a rim or band oftin Gr, G, about four inches wide through which close to each wing arepierced the slits I, I. These slits should be about one inch long eachand three eighths of an inch wide. and should have one inch spacebetween them. It is through these slits that the pictures are to be seenin succession, and that as they advance toward or recede from the eye inthe direction of the line of vision, and within the range of the focusof the prisms. This form of instrument has a great advantage in keepingthe picture in view for a long time for the picture cannot be seenentire through these slits except when the wheel is in motion. when asthe slit is passing before the eye the picture is advancing toward theeye. and its various parts are seen in succession, and yet seems to bequite at rest. To prepare the pictures for this instrument it isnecessary to consider the nature of the motion it is designed torepresent and with this view motions must be divided into two generalclasses, under the names of reciprocating, and rotary motions. The firstclass or the reciprocating motion comprises all simple motions, such asfanning,

three pictures, one of each extreme of the motion, and one of a positionhalfway between these two. Make two of each picture, that is, sixpictiires, and arrange them in the slides of the instrument in thefollowing order: Two of the beginning of the motion,

one of the middle position, two of the end position and one of themiddle position. The reason why the two extreme positions are placed inpairs together is to cause a dwell, or pause at each end of the stroke.Having arranged the pictures in this manner within the instrument uponturning the wheel by means of the knob H and at the same time, andlooking through the prisms.

C, C, the picture will seem at rest except the motion designed to beshown, will appear as natural as life. It is not in this class ofpictures absolutely necessary that there should be six pictures, butthree can be placed in contiguous slides then by attaching a pendulum tothe axis and causing it to vibrate back and forth far enough to showeach of the pictures. The same effect will be produced as if the sixpictures were used.

In representing motions which are included in the second class sixpictures must be made and used in succession. There are again somesubjects too complicated in their motions to be represented by sixpictures. To represent these, more pictures must be taken, and the wheelmust be made larger in diameter and have more wings, or better stilladopt a plan shown in Figs. 2 and 3 of the annexed drawing.

Fig. 2 represents one of the ordinary instrumentsfor exhibitingstereoscopic pictures having two parallel shafts over which pass anendless chain of pictures. To this instrument is, added between the eyepiece D and the picture to be seen a cylinder which cylinder A ispierced by an opening B which is wholly on one side of the center of thecylinder. The cylinder A has also a shield G in'closing one half of itscircumference. The use of this shield is to cover up the openings as isshown in Fig. 3 when the cylinder has made half of a revolution and thussecures the possibility of the opening being seen through only onceduring each revolution of the cylinder. This cylinder is provided with agear wheel to which motion is given by a larger wheel on the top axis ofthe instrument, and which wheel is four times as large as the one on thecylinder. Now as four pictures are thrown over as at F they can only beseen in succession during the time they occupy the relative positions asshown at Fig. 2. This plan will enable a very large series of picturesto be brought into requisition and complicated motions to berepresented. Still another device applicable to the same instrument asis shown in Fig. 2 is to attach the series of pictures flatwise to anendless band of cloth as is shown in Fig. 4E and having the top axisover which they pass provided with a flat plate as wide as the card uponwhich the pictures are mounted, and this plate extending an equaldistance on each side of the axis. By this arrangement two pictures onlywould be brought into view at each turn of the crank and therefore theproportion of the gearing giving motion to the cut off cylinder shouldbe two to one.

The name I design giving .to the instru- -ments embodying the principlesof my invcntion is kinematoscope, which is intended to convey the ideaof I see motion.

I do not wish to limit my claim to any of the special devices abovedescribed (some of which I shall make the subject of patents fordevices) but lVhat I do claim as new and desire to secure by LettersPatent is Combining with the stereoscope a series of pictures arrangedin succession as described when said pictures revolve on an axis atright angles or nearly so to the line of vision, the whole beingconstructed and operated substantially in the manner and for the purposeset forth.

COLEMAN SELLERS.

W'itnesses CHAS. BURNHAM, GEO. BURNHAM.

